Crucible molds

Abstract

Methods for forming a unitized crucible assembly for holding a melt of silicon for forming a silicon ingot are disclosed. In some embodiments, the methods involve a porous crucible mold having a channel network with a bottom channel, an outer sidewall channel that extends from the bottom channel, and a central weir channel that extends from the bottom channel. A slip slurry may be added to the channel network and the liquid carrier of the slip slurry may be drawn into the mold. The resulting green body may be sintered to form the crucible assembly.

What is claimed is: 
     
       1. A crucible mold comprising:
 a lower portion; and 
 an upper portion disposed above the lower portion, the upper portion forming:
 a central weir channel; 
 an inner weir channel; 
 a central weir channel riser that extends through the upper portion and is in fluid communication with the central weir channel; 
 an inner weir channel riser that extends through the upper portion and is in fluid communication with the inner weir channel; and 
 an outer sidewall channel riser that extends through the upper portion, wherein the central weir channel riser, the inner weir channel riser, and the outer sidewall channel riser extend through an upper surface of the crucible mold; and 
 
 
       wherein the upper portion and lower portion togetherform:
   a bottom channel; and   a sidewall channel fluidly connected to the bottom channel and in fluid communication with the outer sidewall channel riser, wherein the central weir channel and inner weir channel extend from the bottom channel and the sidewall channel, the central weir channel, and the inner weir channel are interconnected.   
 
     
     
       2. The crucible mold as set forth in  claim 1  wherein the upper portion comprises a flange, the flange resting on the lower portion. 
     
     
       3. The crucible mold as set forth in  claim 1  wherein the crucible mold is porous. 
     
     
       4. The crucible mold as set forth in  claim 3  wherein the crucible mold is made of porous silica. 
     
     
       5. The crucible mold as set forth in  claim 1  wherein the bottom channel is rounded. 
     
     
       6. The crucible mold as set forth in  claim 1  wherein the upper portion has a main body having lower surface and the lower portion has a main body having an upper surface, the lower and upper surfaces forming the bottom channel and the sidewall channel. 
     
     
       7. The crucible mold as set forth in  claim 6  wherein the upper portion comprises a flange that extends from the main body of the upper portion, the flange resting on the main body of the lower portion. 
     
     
       8. The crucible mold as set forth in  claim 6  wherein at least a portion of the lower surface is rounded and at least portion of the upper surface is rounded. 
     
     
       9. The crucible mold as set forth in  claim 1  wherein each of the central weir channel riser, inner weir channel riser, and outer sidewall channel riser comprises a cone portion and a duct, the cone portion being disposed above the duct and in fluid communication with the duct. 
     
     
       10. The crucible mold as set forth in  claim 1  wherein the central weir channel riser is a first central weir channel riser, the inner weir channel riser is a first inner weir channel riser, and the outer sidewall channel riser is a first outer sidewall channel riser, the upper portion comprising:
 a second central weir channel riser that extends through the upper portion and is in fluid communication with the central weir channel; 
 a second inner weir channel riser that extends through the upper portion and is in fluid communication with the inner weir channel; and 
 a second outer sidewall channel riser that extends through the upper portion and is in fluid communication with the outer sidewall channel riser. 
 
     
     
       11. The crucible mold as set forth in  claim 1  wherein the central weir channel riser, the inner weir channel riser, and the outer sidewall channel riser are aligned.